Search results for "OXIDATION"
showing 10 items of 1913 documents
Iron Fortification of Milk and Dairy Products
2013
Blood haemoglobin level is used to define anaemia. Thresholds are given by category of age, of sex, and also of physiological status such as pregnancy. For example, the threshold is 120 g L–1 of haemoglobin in blood for a nonpregnant adult woman, 110 for a pregnant woman, 130 for a man older than 15 years, 110 for a child under 5 years… Iron deficiency constitutes the most important worldwide problem of human nutrition. In 2005, 1.62 billions of people were concerned by iron deficiency. Iron deficiency is encountered mostly in poor countries and particularly in Western Pacific, except Australia and New Zealand, in India and Pakistan, in the great majority of countries in Africa, in South Am…
Anaerobic oxidation of methane in sediments of a nitrate-rich, oligo-mesotrophic boreal lake
2021
AbstractThe identity of electron acceptors in promoting anaerobic oxidation of methane (AOM) in the sediments of boreal lakes is currently unknown. Here, we studied the AOM rate of sediment slurries collected from three profundal stations of a nitrate-rich, oligo-mesotrophic, boreal lake (Lake Pääjärvi, Finland), under varying nitrate concentrations using 13C-labelling. Furthermore, vertical profiles of the sediment and porewater geochemistry, and the microbial communities (16S rRNA gene and shotgun metagenomic sequencing) were analyzed. Despite geochemical data indicating that simultaneous consumption of nitrate and methane took place at the sediment layers chosen for incubations, AOM rate…
Synthesis and support composition effects on CH4 partial oxidation over Ni–CeLa oxides
2015
Abstract Two series of Ni (6 wt%) catalysts supported over CeO 2 , La 2 O 3 and mixed CeO 2 –La 2 O 3 were prepared by co-precipitation and by wet-impregnation. The effect of the two Ni loading procedures on the catalyst structural properties was investigated by XRD, TPR and XPS. The catalytic behavior of the catalysts was tested in the methane partial oxidation reaction performed at 1 atm in a temperature range of 400–800 °C using dilute feed gas mixture with CH 4 /O 2 = 2 and gas hourly space velocity of 60,000 ml g −1 h −1 . Total methane combustion was observed within the 450 °C ≤ T ≤ 650 °C temperature range. Above 650 °C partial oxidation of methane started to occur, reaching at 80…
Oxidation, efflux, and isotopic fractionation of methane during autumnal turnover in a polyhumic, boreal lake
2007
[1] We studied the oxidation and efflux of methane (CH4) in a small, polyhumic lake, Mekkojarvi (southern Finland), during 6 weeks in autumn when the stability of the water mass first weakened, temporarily restabilized, and finally mixed completely. During the summer stratification period, CH4 had accumulated in the anoxic hypolimnion to high concentrations (>150 mmol m−3). Gradual mixing of the water column during the autumn allowed access to both oxygen and CH4 by aerobic methane-oxidizing bacteria (MOB) deeper in the water column. Thus the bulk (∼83–88%) of the CH4 accumulated in the hypolimnion was subsequently consumed by MOB while only 12–17% was lost from the lake to the atmosphere a…
Environmentally Friendly Photocatalytic Oxidation of Aromatic Alcohol to Aldehyde in Aqueous Suspension of Brookite TiO(2)
2008
WOS: 000260509000008
Effect of compatibilization on the photo-oxidation behaviour of polyethylene/polyamide 6 blends and their nanocomposites
2015
Abstract Polymer based nanocomposites are increasingly attracting interest from academia and industry, and the use of polymer blends as matrices greatly increase their potential field of application. In order to improve their characteristics, the use of compatibilizers acting on the blend components is mandatory. However, this also leads to rising concerns regarding the behaviour of polymer blend based nanocomposites upon being subjected to photo-oxidative degradation. It is known that morphology can deeply influence the photo-oxidative behaviour, and this can be therefore deeply influenced by the blend components and by the use of compatibilizers. In this work, polymer blend nanocomposites…
Oxidant/antioxidant status in obese children compared to pediatric patients with type 1 diabetes mellitus.
2009
Codoner-Franch P, Pons-Morales S, Boix-Garcia L, Valls-Belles V. Oxidant/antioxidant status in obese children compared to pediatric patients with type 1 diabetes mellitus. Background: Type 1 diabetes (T1D) mellitus and obesity are recognized risk factors for cardiovascular disease (CVD). A common mechanism underlying an increased risk for endothelial dysfunction in these two metabolic diseases is oxidative stress. Objective: To evaluate and compare the oxidant/antioxidant defense systems in children affected with T1D or obesity in order to determine the importance of oxidative stress before the emergence of complications. Subjects: Children with T1D (n = 20) or obesity (n = 22), without com…
Cytoprotective effect of resveratrol diastereomers in CHO-K1 cells exposed to beauvericin
2015
Beauvericin (BEA) causes cytotoxicity, lipid peroxidation and reactive oxygen species in CHO-K1 cells. Resveratrol (RSV) is a polyphenol with multiple biological properties, including antioxidant effects. RSV has two forms: trans and cis. The aims of this study were to determine the cytoprotective effect of trans-RSV and diastereomers mixtures (50:50 trans/cis-RSV and 70:30 trans/cis-RSV) incubated alone and in combination with BEA in ovarian (CHO-K1) cells. The results demonstrated that cell viability increases (from 9% to 77%) when they were exposed to low concentration of RSV. Moreover, when the cells were pre-treated with RSV and then exposed to BEA, a cytoprotective effect (from 25% to…
Comparative Investigation on the Soil Burial Degradation Behaviour of Polymer Films for Agriculture before and after Photo-Oxidation
2020
Polymer films based on biodegradable polymers, polyethylene (PE) and modified PE with oxo-degradable additive were prepared by film blowing. Carbon black (1%) was added to all the films. Commercial biodegradable Ecovio®
Formaldehyde: Catalytic Oxidation as a Promising Soft Way of Elimination
2013
International audience; Compared to other molecules such as benzene, toluene, xylene, and chlorinated compounds, the catalytic oxidation of formaldehyde has been studied rarely. However, standards for the emission level of this pollutant will become more restrictive because of its extreme toxicity even at very low concentrations in air. As a consequence, the development of a highly efficient process for its selective elimination is needed. Complete catalytic oxidation of formaldehyde into CO2 and H2O using noble-metal-based catalysts is a promising method to convert this pollutant at room temperature, making this process energetically attractive from an industrial point of view. However, th…